Retirement Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Components of net periodic benefit cost
Service cost	$ 148	$ 126
Interest cost	978	987
United States Pension Plan of US Entity
Components of net periodic benefit cost
Service cost	148	126	$ 288
Interest cost	978	987	851
Expected return on plan assets	(1,671)	(1,573)	(1,485)
Amortization of prior service cost	0	0	8
Amortization of net loss	545	450	917
Settlement cost	0	0	299
Curtailment cost	0	0	252
Net pension (benefit) expense for defined benefit plan	$ 0	$ (10)	$ 1,130